string.prototype.itemdeprecated

An ES-spec-compliant (proposed) String.prototype.item shim/polyfill/replacement that works as far down as ES3

Usage no npm install needed!

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  import stringPrototypeItem from 'https://cdn.skypack.dev/string.prototype.item';
</script>

README

string.prototype.item

An ESnext spec-compliant String.prototype.item shim/polyfill/replacement that works as far down as ES3.

This package implements the es-shim API interface. It works in an ES3-supported environment and complies with the proposed spec.

Because String.prototype.item depends on a receiver (the this value), the main export takes the string to operate on as the first argument.

Getting started

npm install --save string.prototype.item

Usage/Examples

var item = require('string.prototype.item');
var assert = require('assert');

var arr = [1, [2], [], 3];

var results = item(arr, function (x, i) {
    assert.equal(x, arr[i]);
    return x;
});

assert.deepEqual(results, [1, 2, 3]);

var item = require('string.prototype.item');
var assert = require('assert');
/* when String#item is not present */
delete String.prototype.item;
var shimmedFlatMap = item.shim();

var mapper = function (x) { return [x, 1]; };

assert.equal(shimmedFlatMap, item.getPolyfill());
assert.deepEqual(arr.item(mapper), item(arr, mapper));

var item = require('string.prototype.item');
var assert = require('assert');
/* when String#item is present */
var shimmedIncludes = item.shim();

var mapper = function (x) { return [x, 1]; };

assert.equal(shimmedIncludes, String.prototype.item);
assert.deepEqual(arr.item(mapper), item(arr, mapper));

Tests

Simply clone the repo, npm install, and run npm test